What is this aluminum cover / cap?

[stevemitchell]

I am doing a full inventory and categorization of every spare part on the boat and found this shoved away in a corner. It was not something I purchased and was left by the previous owner.

There are no part numbers or other identifying marks and no paperwork or bags with it. It feels like it is made of aluminum and looks like the top of something under pressure. It has an included o-ring.

I have Volvo Penta engines and an Onan generator if that helps identify it. I feel like I’ve seen this before in a smaller version but my mind is filled with useless images of many things....

 

[Lepke]

Looks like the bottom of a filter housing.

 

[stevemitchell]

Looks like the bottom of a filter housing.

Aha yes it does. Hmmm wonder from what. I looked through the engine room and generator and didn’t see anything that looks familiar.

 

[alfamike]

What is it

One sure way to find out what it is -- if you throw it away, you will need it soon there after & it will be very expensive.

if you keep it, you will never need it.

So act wisely.


It looks like the top, or if it is inverted when installed, the bottom of a canister oil filter or hydraulic oil filter housing. Not necessarily from an engine, maybe from a hydraulics system, like active Fins or hydraulic windless or hydraulic steering ? or even fuel filter, etc.

Good Luck.

Alfa Mike

 

[Xsbank]

It looks a lot like the filler cap on my hydraulic reservoir.

 

[healhustler]

Well, whatever it is, better send it out for service and pick up some extra O-rings for it, just in case.

 

[FlyWright]

Looks like the bottom of a filter housing.

My thoughts exactly!

 

[IRENE]

Hydronic heat coolant reservoir cap?

Hydraulic steering reservoir cap?

 

[Dougcole]

As others have said above, it is the bottom bowl of a fuel/water separator filter housing. Most likely for an outboard or maybe a genset. You crack the knurled screw to drain off water. Doesn't look quite like a racor though.


I bet it was used on a dinghy.

 

[stevemitchell]

I'm beginning to think it could have been used on a previous dinghy or engine that is not with the boat now. I checked everything in the engine room one last time, and couldn't see anything like it. I am not going to throw it away or recycle it as that will surely doom me to needing it immediately, I just wanted to know what it was for my inventory, so I could categorize it appropriately. Thanks for the suggestions!

 

[Alaskan Sea-Duction]

Onan generator fuel filter housing.

 

[Ski in NC]

Yep, bottom of Racor spin on fuel filter used on Onan MDKD 8kW gennie.

 

[Alaskan Sea-Duction]

Yep, bottom of Racor spin on fuel filter used on Onan MDKD 8kW gennie.

You can get a NAPA filter with the bowl already part of the filter.

 

[stevemitchell]

Onan generator fuel filter housing.

Aha I have an Onan generator....

Yep, bottom of Racor spin on fuel filter used on Onan MDKD 8kW gennie.

I have an MDKD 9kW Onan

You can get a NAPA filter with the bowl already part of the filter.

Aha! Mystery solved! I have four of those as spares, and one on the engine. So the other one was the older way to do it. Thanks!